436 



SUMMARY or CURRENT EESEARCHES RELATING TO 



arrangement may be applied for special studies. In this paper I have 

 confined my description to those concerned in the application of the 

 Microscope to mineralogy and petrology." 



Konkoly's Microscope for observing^ the Lines in Photog^raphed 

 Spectra.*— Fig. 58 represents the apparatus devised by Dr. N. v. Konkoly 

 on the type of Hilger's instrument for the same purpose, j" 



A A is a nickeled cast-iron base on which are mounted the two 

 perforated supports B B ; these are united by the two frames T and S, 

 of which the former serves as object- stage, while the latter carries the 

 Microscope M. The frame S carries the slide C between swallow-tail 



Fra. 58. 



guides, and upon C the Microscope is fixed by three tension- and three 

 pressure-screws, s is the steel screw which moves the Microscope, and 

 the nut which propels it is the nave of the drum T', which is turned by 

 the milled head g. The screw terminates in a sphere which is inclosed 

 in a socket upon the slide C ; the screw is prevented from turning in 

 the socket by a pin, which does not, however, fit into a hole as is usually 

 the case, but into a slightly elongated slit, so that the screw, with a 



* Central-Ztg. f. Opt. u. Mech., viii. (1887) pp. 241-2 (1 fig.), 

 t See tliis Journal, 1887, p. 461. . 



